1. Field of the Invention
This invention is directed to a protective structure and to a protective system for protecting buildings, streets, and other areas from explosions caused by an explosive device such as a bomb. More particularly, the protective structure and protective system employ a membrane-like mesh structure made up of, for example, steel wire. The mesh structure surrounds a composite fill material such as reinforced concrete. The protective structure deflects in response to and absorbs the energy associated with the blast load of an explosion, and the mesh structure prevents composite fragments from injuring people or property in the vicinity of the explosion. The protective structure may be sacrificial in nature, i.e., its sole purpose is to absorb the energy from the explosive shock wave and contain composite debris caused by the explosion, or the protective structure may be employed as a load-bearing structural component. Accordingly, this results in reduction in personal injury and property damage due to the explosion.
2. Background Information
Protection of people, buildings, bridges etc. from attacks by car or truck bombs, remote controlled explosives, etc. is of increasing importance and necessity. The explosive force or pressure wave generated by an explosive device such as a car bomb may be sufficient (depending on the size of the explosive device used) to disintegrate a composite wall, thereby causing shrapnel-like pieces of composite to be launched in all directions, and causing additional personal injury and property damage.
Conventional reinforced composite structures such as reinforced concrete walls are well known to those skilled in the art. Such conventional structures typically employ steel reinforcement bars embedded within the composite structure or wall. However, in the case of an explosion or blast load which may generate a pressure wave in excess of tens of thousands of psi, a conventional reinforced composite structure will be ineffective in providing sufficient protection, and the blast load will cause disintegration of the composite, thereby causing shrapnel-like pieces of composite to be launched in all directions, and causing additional personal injury and property damage.
One example of a proposed solution for this problem is the Adler Blast Wall™ which, is made up of front and back face plates which contain a reinforced concrete fill material. According to the developers of the Adler Blast Wall™, if an explosion occurs proximate to the front face plate, the back face plate will catch any concrete debris which results from the explosion. However, if the back face plate of the Adler Blast Wall™ is sufficiently displaced in the horizontal or vertical direction due to the explosion, small pieces of concrete debris traveling at high velocities may escape, thereby causing personal injury or property damage. Accordingly, there is a need for a protective structure which further minimizes the possibility that such small pieces of concrete debris traveling at high velocities will escape the protective structure employed.
It is a first object of this invention to provide a blast resistant protective structure which minimizes the possibility that small pieces of concrete debris traveling at high velocities will escape the protective structure in the event of an explosion or blast load proximate to the structure.
It is one feature of the protective structure of this invention that it employs a membrane- like mesh structure made up of, for example, steel wire, and structural steel cables in contact with the mesh structure, for example welded to the mesh structure forming a cage around it, or interwoven into the mesh structure. The mesh structure is compressible in all three dimensions, and surrounds a composite fill material such as reinforced concrete, fiber reinforced plastics, molded plastics, or other composite plastics. In the event of an explosion proximate to the protective structure of this invention, the mesh structure advantageously prevents composite fragments produced due to disintegration of the composite fill material of the protective structure from injuring people or property in the vicinity of the explosion.
It is another feature of the protective structure of this invention that, in the event of an explosion proximate to the protective structure of this invention, the protective structure deflects in response to and absorbs the energy associated with the blast load of the explosion.
It is a second object of this invention to provide a protective system which employs a number of the above described protective structures which are joined together via a number of support members, thereby providing a protective wall of sufficient length to provide more complete protection of a given area as well as additional ease of construction and use. The protective system may be used, but is not limited to use in constructing buildings, tunnels, portals etc.
It is a feature of the protective system of the invention that the support members be capable of receiving the respective ends of the protective structures to provide an integrated wall structure.
It is another feature of the protective system of the invention that the support members may also employ a mesh structure made up of, for example, steel wire. The mesh structure may surround a composite fill material such as reinforced concrete, fiber reinforced plastics, molded plastics, or other composite plastics. Thus, in the event of an explosion proximate to the protective system of this invention, the mesh structure prevents concrete fragments produced due to disintegration of the concrete fill material of the support members from injuring people or property in the vicinity of the explosion.
Other objects, features and advantages of the protective structure and protective system of this invention will be apparent to those skilled in the art in view of the detailed description of the invention set forth herein.